IAD to Asia you've really only got the UA and NH nonstop options. Everything else you're going to have to connect, either domestic or in Europe. And that adds an extra layer of difficulty finding award seats, particularly since domestic UA award availability can be pretty poor.

I am a firm believer that diligent, patient searching will be rewarded. There are still some real pearls out there (including NZ to AKL in J, for the first time in years). Don't forget the option of booking the long-haul (e.g., IAH-NRT or LAX-ICN), taking whatever you can get right now for the domestic connection, and waitlisting for the domestic connection you really want.